This invention relates generally to motorcycle engine ignition systems, and, more particularly, to the provision of supplemental contacts in such system to effect elimination of so-called "dead spark problems".
In conventional dual cylinder motorcycle ignition system, a single set of contact points is employed to fire both cylinders (i.e., produce spark plug ignition of combustible mixtures in each cylinder). Spark plugs at both cylinders are fired together, but only one such firing is effective--the one associated with the cylinder wherein the combustible mixture is compressed by the piston, near piston TDC (top dead center position); the other simultaneous firing is ineffective since that cylinder is at its exhaust mode of operation. This has led to problems with ignition timing, since, if the one set of points was adjustably set for optimum timing for ignition at one cylinder, it was not necessarily then correctly set for optimum timing for ignition at the other cylinder, due to differences in physical characteristics of the two cylinders and in combustible mixture flow to the two cylinders. Engine roughness resulted. Also, in the past, timing adjustment was difficult, requiring one person to control a strobe light, and another person to make the adjustment.
There is need for improvements in contact induced ignition at the spark plugs of two-cylinder, motorcycle engines of the above type.